PEEK Sample Loops avoid many of the problems associated with stainless steel sample loops. Metal loops will often absorb sample components resulting in inaccurate quantitative results. In addition, metal loops may be corroded by high-salt buffers and chloride salts. Sample Loops are made from PEEK tubing andfittings. PEEK (Poly-Ether-Ether-Ketone) is a mechanically strong,chemically inert polymer ideal for HPLC applications where metalsurfaces may interact with mobile phase or sample components. Each Sample Loop is supplied with two PEEK hex-head nuts andferrules. These fittings grip the tubing in two locations for amore reliable connection. Rheodyne Sample Loops are made of natural PEEK. This means nodye leaching into your sample. Like metal loops, the size designations of PEEK loops are nominal. The actual volumes can differ from the theoretical designations because of the ±0.05 mm (0.002") tolerance of the tubing bore. Accuracy of largePEEK loops (0.8 mm, 0.030" bore) is about ±14%, intermediateloops (0.5 mm, 0.020") ±21%, and small loops (0.2 mm,0.007") ±65%. Bore: 0.76 mm